Retractable tunnel-type shuttering

ABSTRACT

Retractable shuttering comprising a pair of frame members for supporting a length of side and top formwork for casting a tunnel, each frame member comprising a pair of side uprights an extensible member connectable between lower end portions of said side uprights and a pair of members each articulated to an upper end of said uprights and articulated to one another at or near the central plane of said tunnel, the pair of members articulated to one of said pairs of uprights extending to the other pair of uprights and being movable vertically along said other pair of uprights, said pair of members being solidly joined by at least one section substantially in the plane of said pair of members to a rack and pinion device to enable lifting or lowering said pair of members respectively to or from an in-line position.

11mm H11 3.61.996

[ 72] inventor Victor Levy FOREIGN PATIENTS Milli? lFmlllc/B 943,658 12/ 1963 Great Britain 61/45 C [21] Appl. No. M 355 1,001,408 2/1952 France 61/45 C Filed 1969 974,865 5/1961 Germany... 61/45 C [45] Patented A g- 1971 V 1,176,085 8/1964 Germany 61/45 C 7 E M iii ts ti l 3] Asslgnee gl fimg gm on S A Primary Examiner-Dennis L. Taylor Attorneyb-Rubert E. Burns and Emmanuel J. Lobato ABSTRACT: Retractable shuttering comprising a pair of [54] WETMWAMLE TUNNELWYPE SHUTTERHNG frame members for supporting a length of side and top tjormmmmgfl nmwmfi Egg work for casting a tunnel, each frame member comprising a pair of side uprights an extenslble member connectable [52] ILLS. Cl 611/45 "C, between lower end portions of said Side uprights and a pair of 243/357 members each articulated to an upper end of said uprights and [51] lllnt. Cl EZM 19/041 articulated to one another at or near the central plane of Said [50] ll ield 01? Search 61/45 R, 45 tune], the pailf members articulaued to one f said pairs f Ci248/354, 357 uprights extending to the other pair of uprights and being movable vertically along said other pair of uprights, said pair [56] Wmlemmw (med of members being solidly joined by at least one section sub- UNITED STATES PATENTS stantially in the plane of said pair of members to a rack and L82 1 ,020 9/1931 Mensforth 61/45 C pinion device to enable lifting or lowering said pair of mem- 2,()36,490 4/1936 Ncilson et al.. 61/45 C v hers respectively to or from an in-line: position.

PATENTEU mm] m SHEET 1 BF 3 RETRACTABLE TUNNEL-TYPE SHU'I'TIERING The use of metal tunnel type shuttering has already been proposed, so forming retractable units allowing rapid shuttering and striking the shuttering of slit building cell bearers and with solid concrete flooring, without previous assembly or dismantling of the constituent elements of the said units.

Such tunnel shuttering is particularly described in French Pat. No. 1,512,440 of 23 Dec. 1966.

The present invention relates to a new tunnel shuttering comprising various improvements with the regard to previous embodiments, with a view to facilitating the shuttering and striking.

According to the invention, there is provided a retractable shuttering comprising a pair of frame members for supporting a length of side and top formwork for casting a tunnel, each frame member comprising a pair of side uprights, an extensible member connectable between lower end portions of said side uprights and a pair of members each articulated to an upper end of said uprights and articulated to one another at or near the central plane of said tunnel, the pair of members articulated to one of said pairs of uprights extending to the other pair of uprights and being movable vertically along said other pair of uprights, said pair of members being solidly joined by at least one section substantially in the plane of said pair of members to a rack and pinion device to enable lifting or lowering said pair of members respectively to or from an inline position.

The characteristics of the present invention will be better understood on reading the following description of one embodiment of the retractable tunnel shuttering relating to the invention, given by way of example and described in reference to the accompanying drawing in which:

FIG. l is a vertical cross section of a tunnel shuttering element in the position for applying the shuttering.

FIG. 2 is a vertical cross section similar to that of FIG. I but showing the said tunnel shuttering element in the striking position.

FIG. 3 is a cross section according to IIl-III of FIG. ll.

On FIG. ll, a tunnel shuttering element can be seen, comprising vertical girders at l and 2, intended to be applied to the side formworks 3 and 4, each consisting of iron plates 3a and 4a, and by channel irons 3b and 4b giving a sufficient rigidity to the said plates 3a and 4a. The girders l and 2 are connected together near their lower ends by means of a crosstie 5, jointed at its extremities to flanges t5 and, in addition, connected to girders l and 2 by means of struts 7 and 8, having articulated joints on the crossties 5 at 7a and on flanges 7b fixed to girders 1 and 2. The length of the struts 7 and 8 is adjustable by means of devices 7c of a known type.

At the lower section of the girders l and 2, shuttering jacks 9 are mounted, to be controlled at a convenient height by an operator. Girders l and 2 are also provided with runnerwheels 10 freely moving about spindles 1 l but in such a way as to be able to stay fixed on the ground, while allowing girders l and 2 to approach one another when a device 5a is actuated to adjust the length of crosstie 5.

A horizontal formwork 12 consists of a metal sheet 12a and reinforcing elements ll2b giving the formwork 12 a sufficient longitudinal strength. This horizontal formwork 12 is joined at its central part by means of stirrup-pieces ll2c with the hinge pivot 13 of various pairs of shears.

The extremities of the elements constituting the shears are jointed at the upper part of channel irons M mounted on girders I and 2 and constitute two parallel flanges between which can be placed a median element of the shears l5, jointed at 116 on the flanges M of the bars ll, or two external shear elements jointed at In on the flanges Ml ofgirders 2.

Struts 17 pass through the lateral walls on either side of the tunnel shuttering.

Two telescopic props l8, placed in the center of the shuttering span, can be immobilized in raised position by means of a pin fitting into the holes is in the two elements, one sliding in relation to the other. Screw devices worked by means of hanlength of the crosstie 5 the two lateral formworks 3 and 4 come away from the vertical walls, which have been newly cast, at the lower part of these walls. It is then sufficient to work the crank handle 24 of a winch to lower a rack and pinion element 25, having an articulated joint on flange 26 sliding on one of the flanges of girder 29, ad acting on the extremity of two horizontal brackets 27 and 27a by means of an articulated channel iron 28. These two brackets 27 and 27a are respectively joined to brackets 30 and 30a, welded to the median elements 15.

These median elements 15 are joined together at their lower parts by a channel iron 31 to which is attached a retaining chain 32 for the pin 230 used in the orifices 23.

In addition, at the upper part of the channel irons l4 strengthening elements 33a are mounted on the edges of the said tunnel shuttering. Elements l5 and 22 also carry adjustable lugs 34 allowing them to be fitted to the exact width of a lifting fork employed to longitudinally move the assembled shuttering unit in the retracted position after the concrete at a particular location has set.

What is claimed is:

l. Retractable shuttering comprising a pair of frame members for supporting a length of side and top formwork for casting a tunnel, each frame member comprising a pair of side uprights, an extensible member connectable between lower end portions of said side uprights and a pair of members each articulated to an upper end of said uprights and articulated to one another at or near the central plane of said tunnel, the pair of members articulated to one of said pairs of uprights extending to the other pair of uprights and being movable vertically along said other pair of uprights, said pair of members being solidly joined by at least one section substantially in the plane of said pair of members to a rack and pinion device to enable lifting or lowering said pair of members respectively to or from an inline position.

2. Shuttering according to claim 1, wherein uprights are supported on jacks.

3. Shuttering according to claim ll, wherein said uprights are supported on wheels to enable approaching together of said uprights upon shortening said extensible member.

4. Shuttering according to claim 1, wherein said section is substantially Y-shaped, each of the arms of the Y being joined to a member, and the tail thereof cooperates with said rack and pinion device.

5. Shuttering according to claim ll, wherein said section 5 substantially V-shaped, each of the arms of said V being joined to a member, and the base thereof cooperates with said rack and pinion device.

6. Shuttering according to claim I, wherein said articulated members are each supported by telescopic struts.

7. Shuttering according to claim 6, wherein said telescopic struts are provided with adjustable stirrups fitting over said extensible members.

3. Shuttering according to claim I wherein said articulated members comprise fittings to enable the lifting of the entire shuttering by means of a forklift truck or the like and its transportation along a tunnel. 

1. Retractable shuttering comprising a pair of frame members for supporting a length of side and top formwork for casting a tunnel, each frame member comprising a pair of side uprights, an extensible member connectable between lower end portions of said side uprights and a pair of members each articulated to an upper end of said uprights and articulated to one another at or near the central plane of said tunnel, the pair of members articulated to one of said pairs of uprights extending to the other pair of uprights and being movable vertically along said other pair of uprights, said pair of members being solidly joined by at least one section substantially in the plane of said pair of members to a rack and pinion device to enable lifting or lowering said pair of members respectively to or from an inline position.
 2. Shuttering according to claim 1, wherein uprights are supported on jacks.
 3. Shuttering according to claim 1, wherein said uprights are supported on wheels to enable approaching together of said uprights upon shortening said extensible member.
 4. Shuttering according to claim 1, wherein said section is substantially Y-shaped, each of the arms of the Y being joined to a member, and the tail thereof cooperates with said rack and pinion device.
 5. Shuttering according to claim 1, wherein said section s substantially V-shaped, each of the arms of said V being joined to a member, and the base thereof cooperates with said rack and pinion device.
 6. Shuttering according to claim 1, wherein said articulated members are each supported by telescopic struts.
 7. Shuttering according to claim 6, wherein said telescopic struts are provided with adjustable stirrups fitting over said extensible members.
 8. Shuttering according to claim 1 wherein said articulated members comprise fittings to enable the lifting of the entire shuttering by means of a forklift truck or the like and its transportation along a tunnel. 